IEC TS 62715-5-4:2019

IEC TS 62715-5-4 ®
Edition 1.0 2019-05
TECHNICAL
SPECIFICATION
colour
inside
Flexible display devices –
Part 5-4: Measuring method of blur in flexible transparent displays
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IEC TS 62715-5-4 ®
Edition 1.0 2019-05
TECHNICAL
SPECIFICATION
colour
inside
Flexible display devices –
Part 5-4: Measuring method of blur in flexible transparent displays

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.120 ISBN 978-2-8322-6928-2

– 2 – IEC TS 62715-5-4:2019  IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 5
4 Measuring conditions . 6
4.1 Standard measuring environmental conditions . 6
4.2 Standard darkroom conditions . 6
4.3 Standard setup conditions . 6
4.3.1 Display mounting . 6
4.3.2 Measuring configuration . 6
4.3.3 Starting conditions of measurements . 7
4.3.4 Conditions of measuring equipment . 7
5 Blur caused by a flexible transparent display . 8
5.1 Purpose . 8
5.2 Measuring conditions . 9
5.3 Measuring method . 9
Annex A (informative) Example of blur measurement configuration . 13
A.1 Purpose . 13
A.2 Examples of parameters in blur measurement . 13
Bibliography . 16

Figure 1 – Geometric configuration of measuring system . 7
Figure 2 – Layout diagram of measurement setup . 8
Figure 3 – Examples of test pattern with and without blur and luminance
measurements . 9
Figure 4 – Schematic diagram to illustrate the method of calculating the standard
deviation specifying the Gaussian blur model . 11
Figure A.1 – Examples of different levels of blur . 13

Table 1 – Example of test report for blur measure . 12
Table A.1 – Examples of the maximum measurement field diameter for different
values of blur width . 14
Table A.2 – Examples of the maximum measurement field diameter for different
values of blur width . 14
Table A.3 – Examples of PPI for different configurations of a reference display device . 14
Table A.4 – Examples of combinations of measurement field diameter and
corresponding distance from the LMD to the reference display device yielding a
measurement field angle of 1° . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FLEXIBLE DISPLAY DEVICES –
Part 5-4: Measuring method of blur in flexible transparent displays

FOREWORD
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Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC TS 62715-5-4, which is a technical specification, has been prepared by IEC technical
committee 110: Electronic displays.

– 4 – IEC TS 62715-5-4:2019  IEC 2019
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
110/1055/DTS 110/1084/RVTDS
Full information on the voting for the approval of this technical specification can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62715 series, published under the general title Flexible display
devices, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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FLEXIBLE DISPLAY DEVICES –
Part 5-4: Measuring method of blur in flexible transparent displays

1 Scope
This part of IEC 62715 specifies the measuring conditions and measuring methods for
determining the blur of objects when viewed through a flexible transparent display. This
document mainly applies to flexible transparent display modules that have a constant radius
curvature about a single axis. The display is measured in a static mechanical state.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 62715-1-1, Flexible display devices – Part 1-1: Terminology and letter symbols
IEC 62715-5-1, Flexible display devices – Part 5-1: Measuring methods of optical
performance
3 Terms, definitions and abbreviated terms
For the purposes of this part of IEC 62715, the terms and definitions in IEC 62715-1-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 Terms and definitions
3.1.1
blur
unclear or indistinct outline of objects when they are viewed through a flexible transparent
display
3.1.2
through-screen pr
...